Traditional Internet Protocol (IP) communication allows a host to send packets to a single host (unicast transmission) or to all hosts (broadcast transmission). To support a demand to provide applications that involve high data rate transmission to multiple hosts, multicast routing has evolved. Multicast routing is used to send data communications to multiple receivers on a network utilizing a multicast address. By sending only a single transmission stream intended for multiple receivers, multicast conserves bandwidth. Thus, multicast is often used to stream audio, video, and other data in a wide range of applications. Source-specific multicast (SSM) is a method of delivering multicast packets in which the only packets that are delivered to a receiver are those originating from a specific source requested by the receiver. By limiting the source, SSM reduces demands on the network and improves security.
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